Answer requests for single announcements

4 files changed, 109 insertions, 46 deletions

diff --git a/ffd/announce.c b/ffd/announce.c
index 151d1b3..ae0a406 100644
--- a/ffd/announce.c
+++ b/ffd/announce.c
@@ -138,3 +138,28 @@ ffd_announce_t* ffd_announce_new(void) {
 
 	return a;
 }
+
+ffd_announce_t* ffd_announce_find(const ffd_node_id_t *node, uint16_t type, uint16_t key) {
+	ffd_announce_t *announce;
+	for (announce = announce_list; announce; announce = announce->next) {
+		if (ffd_are_node_ids_equal(&announce->node, node)
+		    && announce->type == type
+		    && announce->key == key)
+			return announce;
+	}
+
+	return NULL;
+}
+
+ffd_announce_t* ffd_announce_get(const ffd_node_id_t *node, uint16_t type, uint16_t key) {
+	ffd_announce_t *announce = ffd_announce_find(node, type, key);
+
+	if (!announce) {
+		announce = ffd_announce_new();
+		announce->node = *node;
+		announce->type = type;
+		announce->key = key;
+	}
+
+	return announce;
+}
diff --git a/ffd/ffd.c b/ffd/ffd.c
index f5b3271..f82932a 100644
--- a/ffd/ffd.c
+++ b/ffd/ffd.c
@@ -198,7 +198,7 @@ static void handle_tlv_ack_req(const ffd_tlv_ack_req_t *tlv_req, size_t len, han
 
 	ffd_neigh_t *neigh = get_tlv_neigh(arg);
 
-	ffd_send_ack(arg->iface, neigh, ntohs(tlv_req->nonce));
+	ffd_send_ack(neigh, ntohs(tlv_req->nonce));
 }
 
 static void handle_tlv_hello(const ffd_tlv_hello_t *tlv_hello, size_t len, handle_tlv_arg_t *arg) {
@@ -284,24 +284,6 @@ static void handle_tlv_node_id(const ffd_tlv_node_id_t *tlv_node_id, size_t len,
 	arg->node_id = tlv_node_id->id;
 }
 
-static ffd_announce_t* get_announce(const ffd_node_id_t *node, uint16_t type, uint16_t key) {
-	ffd_announce_t *announce;
-	for (announce = announce_list; announce; announce = announce->next) {
-		if (ffd_are_node_ids_equal(&announce->node, node)
-		    && announce->type == type
-		    && announce->key == key)
-			return announce;
-	}
-
-	/* not found */
-	announce = ffd_announce_new();
-	announce->node = *node;
-	announce->type = type;
-	announce->key = key;
-
-	return announce;
-}
-
 static ffd_nexthop_t* find_nexthop(const ffd_announce_t *announce, ffd_neigh_t *neigh) {
 	ffd_nexthop_t *nexthop;
 	for (nexthop = announce->nexthop_list; nexthop; nexthop = nexthop->next) {
@@ -342,7 +324,7 @@ static void handle_tlv_update(const ffd_tlv_update_t *tlv_update, size_t len, ha
 
 	fprintf(stderr, "debug: update received from %04x%04x.\n", ntohl(*(uint32_t*)arg->node_id.id), ntohl(*(uint32_t*)(arg->node_id.id+4)));
 
-	ffd_announce_t *announce = get_announce(&arg->node_id, ntohs(tlv_update->type), ntohs(tlv_update->key));
+	ffd_announce_t *announce = ffd_announce_get(&arg->node_id, ntohs(tlv_update->type), ntohs(tlv_update->key));
 	ffd_metric_seqno_t ms = { ntohs(tlv_update->metric), ntohs(tlv_update->seqno) };
 	bool feasible = ffd_is_feasible(announce, ms);
 
@@ -387,13 +369,17 @@ static void handle_tlv_announce_req(const ffd_tlv_announce_req_t *tlv_req, size_
 		return;
 	}
 
-	ffd_announce_t *announce = NULL;
-
-	if (!ffd_is_node_id_unspec(&tlv_req->node)) {
-		announce = NULL;
+	if (ffd_is_node_id_unspec(&tlv_req->node)) {
+		ffd_send_update(NULL, get_tlv_neigh(arg), NULL, tlv_req->flags & FFD_UPDATE_WITH_DATA);
 	}
+	else {
+		ffd_announce_t *announce = ffd_announce_find(&tlv_req->node, ntohs(tlv_req->type), ntohs(tlv_req->key));
 
-	ffd_send_update(arg->iface, get_tlv_neigh(arg), announce, tlv_req->flags & FFD_UPDATE_WITH_DATA);
+		if (announce)
+			ffd_send_update(NULL, get_tlv_neigh(arg), announce, tlv_req->flags & FFD_UPDATE_WITH_DATA);
+		else
+			ffd_send_retract(get_tlv_neigh(arg), tlv_req->node, ntohs(tlv_req->type), ntohs(tlv_req->key));
+	}
 }
 
 static void handle_tlv(ffd_tlv_type_t type, const void *data, size_t len, void *arg) {
diff --git a/ffd/ffd.h b/ffd/ffd.h
index 91a9dbb..43cb809 100644
--- a/ffd/ffd.h
+++ b/ffd/ffd.h
@@ -186,10 +186,13 @@ static inline bool ffd_is_feasible(const ffd_announce_t *announce, ffd_metric_se
 void ffd_announce_update(ffd_announce_t *announce);
 void ffd_announce_update_nexthop(ffd_announce_t *announce, ffd_nexthop_t *nexthop, ffd_metric_seqno_t ms, uint16_t interval);
 ffd_announce_t* ffd_announce_new(void);
+ffd_announce_t* ffd_announce_find(const ffd_node_id_t *node, uint16_t type, uint16_t key);
+ffd_announce_t* ffd_announce_get(const ffd_node_id_t *node, uint16_t type, uint16_t key);
 
-void ffd_send_ack(ffd_iface_t *iface, ffd_neigh_t *neigh, uint16_t nonce);
+void ffd_send_ack(ffd_neigh_t *neigh, uint16_t nonce);
 void ffd_send_hellos(void);
 void ffd_send_update(ffd_iface_t *iface, ffd_neigh_t *neigh, ffd_announce_t *announce, bool with_data);
+void ffd_send_retract(ffd_neigh_t *neigh, ffd_node_id_t node, uint16_t type, uint16_t key);
 void ffd_send_announce_request(ffd_iface_t *iface, ffd_neigh_t *neigh, ffd_node_id_t node, uint16_t type, uint16_t key, bool with_data);
 
 #endif /* _FFD_FFD_H_ */
diff --git a/ffd/send.c b/ffd/send.c
index 97ff3f1..283b36e 100644
--- a/ffd/send.c
+++ b/ffd/send.c
@@ -40,7 +40,7 @@
 #include <sys/uio.h>
 
 
-static bool send_eth(const eth_addr_t *addr, unsigned ifindex, void *buf, size_t len) {
+static bool send_eth(const eth_addr_t *addr, unsigned ifindex, const void *buf, size_t len) {
 	static const uint8_t zeros[46] = {0};
 
 	struct sockaddr_ll sa;
@@ -52,7 +52,7 @@ static bool send_eth(const eth_addr_t *addr, unsigned ifindex, void *buf, size_t
 	memcpy(sa.sll_addr, addr->d, ETH_ALEN);
 
 	struct iovec vec[2] = {
-		{ .iov_base = buf, .iov_len = len },
+		{ .iov_base = (void*)buf, .iov_len = len },
 		{ .iov_base = (void*)zeros, .iov_len = sizeof(zeros) - len },
 	};
 
@@ -72,7 +72,43 @@ static bool send_eth(const eth_addr_t *addr, unsigned ifindex, void *buf, size_t
 	return true;
 }
 
-void ffd_send_ack(ffd_iface_t *iface, ffd_neigh_t *neigh, uint16_t nonce) {
+static inline bool send_neigh(const ffd_neigh_t *neigh, const ffd_packet_t *packet) {
+	if (!neigh->iface)
+		return false;
+
+	if (!send_eth(&neigh->addr, neigh->iface->ifindex, packet, sizeof(ffd_packet_t)+ntohs(packet->len))) {
+		fprintf(stderr, "send_eth: %m\n");
+		return false;
+	}
+
+	return true;
+}
+
+static inline bool send_iface(const ffd_iface_t *iface, const ffd_packet_t *packet) {
+	if (!send_eth(&ffd_addr, iface->ifindex, packet, sizeof(ffd_packet_t)+ntohs(packet->len))) {
+		fprintf(stderr, "send_eth: %m\n");
+		return false;
+	}
+
+	return true;
+}
+
+static inline void send_broadcast(const ffd_packet_t *packet) {
+	ffd_iface_t *iface;
+	for (iface = iface_list; iface; iface = iface->next)
+		send_iface(iface, packet);
+}
+
+static inline void send_any(const ffd_iface_t *iface, const ffd_neigh_t *neigh, const ffd_packet_t *packet) {
+	if (neigh)
+		send_neigh(neigh, packet);
+	else if(iface)
+		send_iface(iface, packet);
+	else
+		send_broadcast(packet);
+}
+
+void ffd_send_ack(ffd_neigh_t *neigh, uint16_t nonce) {
 	ffd_packet_t *packet = alloca(sizeof(ffd_packet_t)+FFD_PACKET_MAX);
 
 	packet->version_magic = htons(FFD_VERSION_MAGIC);
@@ -84,8 +120,7 @@ void ffd_send_ack(ffd_iface_t *iface, ffd_neigh_t *neigh, uint16_t nonce) {
 
 	ack->nonce = htons(nonce);
 
-	if (!send_eth(&neigh->addr, iface->ifindex, packet, sizeof(ffd_packet_t)+ntohs(packet->len)))
-		fprintf(stderr, "send_eth: %m\n");
+	send_neigh(neigh, packet);
 }
 
 static void add_ihus(ffd_packet_t *packet, size_t max_len, const ffd_iface_t *iface) {
@@ -127,8 +162,7 @@ void ffd_send_hellos(void) {
 
 		add_ihus(packet, FFD_PACKET_MAX, iface);
 
-		if (!send_eth(&ffd_addr, iface->ifindex, packet, sizeof(ffd_packet_t)+ntohs(packet->len)))
-			fprintf(stderr, "send_eth: %m\n");
+		send_iface(iface, packet);
 	}
 }
 
@@ -192,11 +226,6 @@ void ffd_send_update(ffd_iface_t *iface, ffd_neigh_t *neigh, ffd_announce_t *ann
 	packet->version_magic = htons(FFD_VERSION_MAGIC);
 	packet->len = 0;
 
-	const eth_addr_t *addr = &ffd_addr;
-
-	if (neigh)
-		addr = &neigh->addr;
-
 	if (announce) {
 		add_update(packet, FFD_PACKET_MAX, NULL, announce, with_data);
 	}
@@ -206,8 +235,7 @@ void ffd_send_update(ffd_iface_t *iface, ffd_neigh_t *neigh, ffd_announce_t *ann
 		ffd_announce_t *a;
 		for (a = announce_list; a; a = a->next) {
 			if (!add_update(packet, FFD_PACKET_MAX, &node_id, a, with_data)) {
-				if (!send_eth(addr, iface->ifindex, packet, sizeof(ffd_packet_t)+ntohs(packet->len)))
-					fprintf(stderr, "send_eth: %m\n");
+				send_any(iface, neigh, packet);
 
 				node_id = FFD_NODE_ID_UNSPEC;
 				packet->len = 0;
@@ -220,10 +248,32 @@ void ffd_send_update(ffd_iface_t *iface, ffd_neigh_t *neigh, ffd_announce_t *ann
 		}
 	}
 
-	if (packet->len) {
-		if (!send_eth(addr, iface->ifindex, packet, sizeof(ffd_packet_t)+ntohs(packet->len)))
-			fprintf(stderr, "send_eth: %m\n");
-	}
+	if (packet->len)
+		send_any(iface, neigh, packet);
+}
+
+void ffd_send_retract(ffd_neigh_t *neigh, ffd_node_id_t node, uint16_t type, uint16_t key) {
+	ffd_packet_t *packet = alloca(sizeof(ffd_packet_t)+FFD_PACKET_MAX);
+
+	packet->version_magic = htons(FFD_VERSION_MAGIC);
+	packet->len = 0;
+
+	if (!add_node_id(packet, FFD_PACKET_MAX, node))
+		return;
+
+	ffd_tlv_update_t *req = ffd_tlv_add(packet, FFD_PACKET_MAX, TLV_UPDATE, sizeof(ffd_tlv_update_t));
+	if (!req)
+		return;
+
+	req->flags = 0;
+	req->reserved = 0;
+	req->interval = htons(FFD_UPDATE_INTERVAL);
+	req->seqno = 0;
+	req->metric = 0xffff; /* no need to htons */
+	req->type = htons(type);
+	req->key = htons(key);
+
+	send_neigh(neigh, packet);
 }
 
 void ffd_send_announce_request(ffd_iface_t *iface, ffd_neigh_t *neigh, ffd_node_id_t node, uint16_t type, uint16_t key, bool with_data) {
@@ -245,6 +295,5 @@ void ffd_send_announce_request(ffd_iface_t *iface, ffd_neigh_t *neigh, ffd_node_
 	if (with_data)
 		req->flags |= FFD_UPDATE_WITH_DATA;
 
-	if (!send_eth(&ffd_addr, iface->ifindex, packet, sizeof(ffd_packet_t)+ntohs(packet->len)))
-		fprintf(stderr, "send_eth: %m\n");
+	send_any(iface, neigh, packet);
 }